Epstein family from Polotsk #belarus

Debby Myers

I am searching for information on the Epstein family from Polotsk. My grandfather and his brother -Zalman and Pinchus- were born and lived in Polotsk and came to Cape Town South Africa in the 1920s- they had been living in Nevel since after WW1 and it was from there that they came to South Africa. They left behind family in Polotsk particularly 2 brothers -Goodman and Arachmiel. One of whom  was involved in the Communist Party. Their father was Shmuel, a teacher, and their mother I think was Dina. The Epstein family was also somehow related to the Postowsky family from Polotsk. If anyone has any connection to above names, would be delighted to hear from you. 
Drbby Myers
Cape Town, South Africa